A known approach to advanced technology fabrication of materials, such as semiconductor substrates, is to assemble a manufacturing facility as a “cleanroom.” In such cleanrooms, processing tools are arranged to provide aisle space for human operators or automation equipment. Exemplary cleanroom design is described in: “Cleanroom Design, Second Edition,” edited by W. Whyte, published by John Wiley & Sons, 1999, ISBN 0-471-94204-9, (herein after referred to as “the Whyte text”).
Cleanroom design has evolved over time from an initial starting point of locating processing stations within clean hoods. Vertical unidirectional airflow can be directed through a raised floor, with separate cores for the tools and aisles. It is also known to have specialized mini-environments which surround only a processing tool for added space cleanliness. Another known approach includes the “ballroom” approach, wherein tools, operators and automation all reside in the same cleanroom.
Evolutionary improvements have enabled higher yields and the production of devices with smaller geometries. However, known cleanroom design has disadvantages and limitations.
For example, as the size of tools has increased and the dimensions of cleanrooms have increased, the volume of cleanspace that is controlled has concomitantly increased. As a result, the cost of building the cleanspace, and the cost of maintaining the cleanliness of such cleanspace, has increased considerably. Not all processing steps, like for example the steps used to assembly products into their packaging, need to occur in the developing large processing environments.
Additionally, the processing of high technology products may typically be split into portions that require high levels of cleanliness in the manufacturing environment which are typically at the beginning of the processing and then steps like the assembly steps which have less critical contamination sensitive processing. In some cases these two types of processing steps may be processed in different facilities because of their different needs. Yet, in many small volume activities, the need for rapid processing of all steps to result in a product that can be utilized in its fully processed form may be important. It would therefore be useful to have an efficient processing fabricator design that can process the different types of steps of multiple cleanliness requirements in a single location with rapidity.